ĐK:\(x^2-x-2\ge0\Leftrightarrow\left[{}\begin{matrix}x\le-1\\x\ge2\end{matrix}\right.\)
\(PT\Leftrightarrow\sqrt{x^2-x-2}-1+2x^2-2x-6=0\)
\(\Leftrightarrow\frac{x^2-x-3}{\sqrt{x^2-x-2}+1}+2\left(x^2-x-3\right)=0\)
\(\Leftrightarrow\left(x^2-x-3\right)\left(\frac{1}{\sqrt{x^2-x-2}+1}+2\right)=0\)
Vì \(\frac{1}{\sqrt{x^2-x-2}+1}+2>0\) \(\Leftrightarrow x^2-x-3=0\)\(\Leftrightarrow x=\frac{1\pm\sqrt{13}}{2}\) (tm)
Vậy...
giai cac phuong trinh
a)\(2x^4+5x^3+x^2+5x+2=0\)
b)\(\sqrt{x-1}-\sqrt[3]{2-x}=1\)
c)\(x-\sqrt{x}+1=\sqrt{2x^2-30x+2}\)
d)\(2x^2+3x+7=\left(x-5\right)\sqrt{2x^2+1}\)
e)\(\sqrt{x-2}+\sqrt{4-x}=2x^2-5x-1\)
Giải phương trình:
a) \(\sqrt{x-2+\sqrt{2x-5}}+\sqrt{x+2+3\sqrt{2x-5}}=7\sqrt{2}\).
b) \(x^2-4x=\sqrt{x+2}\), với \(x\ge2\).
c) \(x^2-7x+2\left(x-2\right)\sqrt{x+1}+1=0\).
Giải hệ phương trình :
\(\left\{{}\begin{matrix}4\left(2x\sqrt{2x-1}-y^3-3y^2\right)=15y+7+\sqrt{2x+1}\\\sqrt{\frac{y\left(y+2\right)}{2}}+\sqrt{6-x}=2x^2+2y^2-15x+4y+12\end{matrix}\right.\)
1. giải các phương trình :
a/\(\sqrt{6x^2-12x+7}=x^2-2x\)
\(\frac{2}{\sqrt{3+x}}=\frac{\sqrt{3+x}}{x-1}\)
c/\(x^2+\sqrt{-x-1}=4+\sqrt{-x-1}\)
d/\(\frac{3x^2+1}{\sqrt{x-1}}=\frac{4}{\sqrt{x-1}}\)
e/\(\sqrt{-x^2+3x+4}=2x^2-6x+2\)
f/\(\frac{\sqrt{4x^2+7x-2}}{x+2}=\sqrt{2}\)
Giải phương trình: \(x^2+3-x\sqrt{2x-1}=3x\sqrt{2x^2-5x+2}-\sqrt{x-2}\)
Bài 8 Tìm tập xác định của hàm số
a , \(y=\frac{x+3}{2x-1}\)
b , \(y=\sqrt{3x+2}+\sqrt{4-x}\)
c , \(y=\frac{\sqrt{7-2x}}{\left(x+1\right)\sqrt{x^2-4x+3}}\)
GHPT :
\(\left\{{}\begin{matrix}\sqrt{5x^2+2xy+2y^2}+\sqrt{2x^2+2xy+5y^2}=3\left(x+y\right)\\3x\left(y-7\right)+10=\sqrt{10x-2}+2\sqrt{8y-3}\end{matrix}\right.\)
a) \(\sqrt{2x+3}\sqrt{x+1}=3x+2\sqrt{\left(2x+3\right)\left(x+1\right)}-16\)
b) \(\sqrt{3x-2}+\sqrt{x-1}=4x-9+2\sqrt{3x^2-5x+2}\)
a, giải pt 1, \(\sqrt{x+4}+\sqrt{x-4}=2x-12+2\sqrt{x^2-16}\)
2, \(\sqrt{2x+1}+3\sqrt{4x^2-2x+1}=3+\sqrt{8x^3+1}\)
b, giải hpt 1, \(\left\{{}\begin{matrix}x^2+4y^2-5=0\\4x^2y+8xy^2+5x+10y-1=0\end{matrix}\right.\)
2, \(\left\{{}\begin{matrix}x^2-2x+2y-3=0\\16x^2-8xy^2+y^4-2y+4=0\end{matrix}\right.\)
